Electrical conducting system.



'W, E. ATHBARN.

ELECTRICAL CONDUCTING SYSTEM.

APPLICATION FILED APR. 29. 1908.

Patented Nov. 23, 1909.

3 S BETH-SHEET 1.

M 66% wx W. E. ATHEARN.

ELECTRIGAL CONDUCTING SYSTEM.

APPLICATION II-LED APR. 29 1908.

3 SHBETS*SHEET 2.

Fig. 2.

INT/6126022 W. E. ATHEARN. ELECTRICAL CONDUCTING SYSTEM.

APPLICATION FILED APR. 29. 1908. I

Patented Nov. 23, 1909.

3 SHEETS-SHEET 3.

UNITED snares rirrnuir enrich.

WILLIAM E. ATHEABN, 0)? NEW YGRK, N. Y., ASSIGNOB T0 AMERICAN. TELEPHONE AND TELEGBAEH 6011i PANY, A CORPORATIGN OF NEW YQRK.

ELECTRECEL CONDUCTING SYSTEM.

implication filed limit 29, 1908. Serial No. 4125,91 4.

trains at high speeds. These power systems. frequently operate Wltll' excessive currents and at a :relatively low frequency, say

twenty-fivecycles,and have been found sometimes to setup in adjacent conductors electromotive forces often. amounting to from one hundred and fifty to three hundred volts and sometimes reaching eight hundred volts. Under such conditions a' grounded tele ra'phic circuit, as usually organized, is reniered inoperative, the induced twentyfive cycle current, even if not under much pressure, causing the relay arnialures to so vibrate that the Morse signals are endered unintelligible. vVith metallic circuits, as those of the telephone, no matter how carefully they are transposed, they still may be seriously aifected when the induced electroinotive force reaches about two hundred volts, since it then begins to discharge at the lightning arresters, and to thedisturhance thus produced is added the hazard ol lire from insutlicient insulation and of painful shocks to subscribers and operators. To prevent these dih'icnltics, it has been proposed to diminish the inductive eli'ec-ts by applyin to the histurbed conductors opposing electroniotive i'orces generated in the plural secondary'windings of one or more properly designed induction coils, there being one of these secondary windings coniieiltod in each signaling conductor, While a primary winding for inducing in the secondaries the neutralizing forces is in a circuit under the same induct ive influence as said signaling conductors. To attain thebest results the resistance of the primary circuit of each induction coil must. be low, and therefore the primary Winding consists of a conductor of relatively lufgelcross section. To continue this low electron'iotive resistance throughout the circuit of the primaries, the coi'iductors making up the remainder of this neutralizing circuit must also he of small resistance, and. since, already pointed out, their exposure must he the same as that Oil the lines in wliich'disturhances are to he abated, it has been found convenient to. set aside from the latter a suliicient number to give the requisite conductivity, connecting these in multiple to each priniaiy winding and grounding their extremities outside the 'alicctcd district to permit a How oi the primary neutralizing current. it will be evident that the lines thus employed are useless for the purposes for which they were intended, since their connection with the single primary winding makes them in eliect a single conductor and the, ground connections carry off the signaling as well as the neutralizing currents. There must consequently be counted against this system, in addition to the comparatively small investment in induction coils, charges for the neutralizing conductors amounting to at least twenty-five per cent. of the 6X penditure for those protected. Though a gain is made, it is at a heavy cost, and the purpose or the present invention is to mimnnze this loss in conductors. With this end in view, my invention con- Eatented Nov. 23,

sists in a means of utilizing for transmission the primary conductors, and ahating therein the effect of the directly induced electronictive forces which develop in the secondary conductors the neutralizing electroinotive forces.

In the accompanying drawings, Figure 1 illustrates diagrammatically one embodiment of my invention; Fig. 2 is a front elevation 0 3 a transformer adapted for use in the system; Fig. 8 is a side elevation of said transformer, and Fig. 4; is a diagram show ing another arrangement'of the system from that of Fig. 1.

Similar characters are applied to like parts throughout the figures of thedrawings'.

Referring particularly to Fig. 1, a grounded power conductor Z, for high potential,

low frequency alternating current, is shown extending in proximity and substantially parallel to a number of conductors L I),

which it is desired to employ for telephonic and telegraphic communication. It may he assumed that the conductors L, l), are

no I

practically equidistant from Z. In the present' instance the conductors are arranged in twisted pairs, and .are therefore adapted for metallic telephone circuits, but they may be also ,used independently of their application to telephone purposes or simultaneously 'therewith for grounded telegraph circuits,

' designated as L, L", respectively. I have shown three times as many conductors in the group b as in a, with the former distributed upon opposite sides of the last named group. In practice, as has already been pointed out,

the distance of each pair of conductors in both groups fromthe disturbing conductor would be substantially the same, all the signalin conductors, for-example, being containe in a cable. In group a the conductors L- are multipled together and have connected with them in series a single low resistance primary winding t of at least one induction coil or transformer T. At points beyond theends of the power conductor the line conductors of group ,a are connected to ground or other common return at G,-G through apparatus which will be later considered, since it does not enter into the operation of th t portion of the system now.

being described. Each transformer has a plurality of secondary windings each consisting of a pair of conductors, and preferably equaling in number the airs in the line group b. The design 0 the transformer is governed by the following gen.- eral considerationsz'The assage of the disturbing current through t e conductor Z will induce in each of the signaling conductors L and L substantially equal electromotive forces. 'In the primary group a this electromotive force will cause a flow of current through the circuit, completed bg the common return, which, traversing t 'e primary windings t of the transformers, generates an electromotive force in each of the secondary windings 't. The secondary windings are so related to the primaries and so connected to the conductors L", that the transformerelectromotive force of the secondary conductors opposes that directly induced by the power conductor. secondary coil with a greater number of turns than its primary to provide for losses in the primary conductors and in transformation, this secondary electromotive force may be made practically to nullify the disturbing 'electromotive force. Complete com- .I hen by supplying eachemcee may be minimized by the use of an efficient transformer and by keeping down thereslstance of the primary circuit, the latter condition being obtained by the large primary winding and the 'multipling with it of a number of the line conductors L The number of transformers used depends upon the length of the groups of lines to be protected and the magnitude of the electrometive force induced, since each of said transformers will carry its proportionate part of thetotal voltage, and -to distribute this among a plurality of transformers increases the factor of safety in case of accident. the present instance two of these are shown, and the primary windings of these transformers may be considered to separate the conductors L into three sections.

I It will be seen that the above system will adapt the conductorsL for both metallic circuit telephone and grounded circuit telegraph purposes between stations of which two are indicated at A. and B on each of two two more important features, these being that each of the lines or circuits of group a are rendered electrically continuous inde pendently oi the assoclated lines in said group and of the windings of the transformers, and that thereis provided for the neutra'llzing prlm'ary current a path to the common return which shall exclude operatin currents. In the j system as illustrated, secure .the continuity of each pair of con ductors by associating their successive sections independently of the primaries of the transformer through repeating coils R having electrically symmetrical sectional Windings r, a, and r, 1". The opposite extremities of the primary t of each transformer .T

are joined in multiple with the centers of the A windings of all the repeating coils connected to the samepair of line sections, that is, to points at the junctures of the coil sections r, 1-, and r 9*, by conductors 10 and 11, respectively." Electrical signaling impulses of a uls'atory or alternating character, such as to ephone currents, ori inated, for exam is, at a station A", flow in both sides of the rst section in the circuit furnished b a pair of conductors L, passing serially t rough the prime y i i equal in r: -'h' r 1111pi" l'ilfiil'fi" fierce iii might, under con senses dncing; siinihir er \vinchi n fission 'Wiii thus continue are 15; he scei'tirni .i fi, each wnnlrn riinnry and r (15% the lHdUGi-lflil coil the reiticn e6. when the trensn ion cccurs in the epncsize direction. The ininicevi pr'r icnls ire ne ccnclnciors L in hnih sections of the wincli sear-(in coil cenclnciicr the first 50 Oil the pewr com both ies of the line weir tions of the repeating; coil be balanced an 7 operafii ng current "io furnish 2i seiective gl'k'llilld connect-inn l h a "re sh ewn for the nenirelizing cnrn n each iine pc i of "line u (.li'lCijfll' Z, a suitable impede?" ceni'er unir-ezl to the grcuncl e coil l c a can 152. 'l' the teiephcne cnrrcni's passing in s we direction throng iheir entire iei'igth these coils present so high an impedance as to be practically eprque or exclusive thereto. bill for inc induced current flowing in opposite directions ti rough the l'nrlves, they m diiierentiaily and become readily poi-nussix 2. in this manner opera-ting: currents are con fined i0 ihe metallic circuit in which they are originated, Whi c e 7 primary neneralic circnimes n. the conrlnctnrs lieu: 'i-hrcngh the common ground in when h imliciiion of slick-primaries will generate.

electromeiive force enposing the ii Poi? irn n' is? eleci'ronmiive force-mu! approaching; in magniiinzle. the ciifiercnce being the necessary in semi iihe irzn'isfornier Volta ing currentihrough the primary inagneiiz the cne another. Such a transformer as inightcomely he need-is shown in 2 and of din'wings. Jiiere a rectangular core built up Of isininre 01f set-ft iron has upon its cpposiie longer sides ihe primary winding 73 distributed uniformly. This primary is furnished by three hundred and fifty turns c1 insnlahad copper tape, having sec iienel dimensions of seventy -two thensenciths cf an inch by one and three-tenths inches and a teial resistance of about fenn iienrhs iii an ohn'r fiver this the phirnl secondaries t are placed side by side on both. cares, each having" the same number of turns of paired windings the prin'inry and being of number tweniyinsnhncri ceppcr wire, each. 033 These Wires presenting; a re sistsnce of eppi ordinate i3 five and seventyfive hhndreclihs chins. Taps are brought out from the prinmrg'g' winding, whereby the number cf warns may he rcclnced by amounts varying up to client fifteen per cent. of the mini to give the desired ratio of transformation. The repeating coils and impedance coils need not be particniaiiiy described, as standard apparatus may be employed.

It will he nmlersroml that my improved system may hemoclificd in many respects witheut departing from the-spirit of the invention.

in L I have ii'nlicaiied (iiegrmnmsh icaiiy an arrengenientin which inst-end of a single repezrtin cell at each transformer gnnling circuit from line section of each pair of pri- 1's, repeating coils R and Each coil has one sectional jieineii in series with the conene iine section, while the other in series with one V 3 r e placed nn-cther ray cer inc-tors 1 1b, The primary :5 each. transformer is united at one exiremii-y h centimeter 1' with the juncture of ihe 'winriings '2', r of zinc coils R whilerhe opposite end of the primary is similarly conncci'eci by a conductor 15 re the Windings r cf the coils R. As in the organ imtion of ig. 1, the neutralizing primary current flows through the conductors of each line pair in pninllel, inwnrci through the winding 7*, 1*" of coil BF, coninctor 14, pri mar 05 the transformer, condncier 15, out- Warcl by" winding r of? ceii I51 and en through the circuit as has been previously traced, and then upon alternation in the opposite direction. The signaling currents circulating in a hne section traverse the winding 7*, r of coil R serially, inducing like currents in the winding 4, and this flows in the circuit formed therewith by the conductors 13, 13 and Winding 1' of coil R the last-named winding repeating into the .winding 1' 9 of coil E Save as indicated, this arrangement operates in the same manner as that of Fig. 1.

In my application, Serial Number 429,973, filed April 29th, 1908, I have claimed a method described but not claimed herein.

I claim:

1. An electrical signaling system comprising groups of lines, an induction coil having a primary winding connected to the lines of one group and secondary windings joined to the lines of a second group, and means for preserving the electrical continuity of each line of the primary group independently of the associated lines.

2. The combination with conducting circuits, of an induction coil having a winding connected to the circuits and dividing them into sections, and means for transmitting electrical impulses from section to section independently of the induction coil.

3. An electrical system comprising a plurality of conductors, a transformer having a primary winding and a plurality of secondary windings, a portion of the conductors being connected in parallel to the primary winding and other conductors united sep arately to the secondary windings, and means outside the transformer for permitting the flow of current through each of the conductors united to the priinary winding.

42., The combination with a plurality of conductors and a common return conductor,

of an induction coil having a primary winding connected in parallel with a plurality of the conductors and dividing them into sections and being provided with secondary windings joined to other conductors, repeating coils for electrically associating the conductor sections at opposite sides of the primary winding, and connections from the primary conductors to the common return conductor, said connections acting select ively with res ect to the currents passing through the vending of the induction coil and those transmitted by the repeating coils.

5. In a signaling system subjected to induction from a source external thereto, the combination with two groups of conductors, of a transformer having a primary winding connected in one group of conductors, a secondary winding connected in the other group, said transformer being organized to generate under the influence of the external source upon the primary conductors an electro-m0tive force in the secondary winding opposing that caused by the external source, means for securing independent paths for the signaling currents through the primary conductors, and ground connections for induced currents from the primary conductors, said ground connections being situated at opposite sides of the transformer and being impassable to the said signaling currents.

In testimony whereof, I have signed my name to this specification in the presence oi. two subscribing Witnesses, this 23rd day of April 1908. I 7

WILLIAM E. ATHEARN.

lVitnesses:

tonnn'r Fos'rnn JANEs, SYLvANUs H. Conn. 

